It has been described as an Easter miracle, three men surviving after their helicopter crashed into the Southern Ocean.

The trio, pilot Andrew Hefford, crewman Lester Stevens, and paramedic John Lambeth were en route to rescue someone off a fishing boat near the Auckland Islands, but ended up being rescued themselves.

The alarm was raised shortly after 8pm last night when they failed to arrive.

After a frantic search for the three men, the wreckage of their helicopter was discovered and a few hours later, the men were found alive walking along the beach.

Dave Greenberg, a former Rescue Helicopter crewman, spoke to Seven Sharp about the crash and the incredible survival of all three men on board.

"I was astonished. When I heard there was wreckage and that there was no personal locator beacon signals, I didn't hold a lot of hope, so very excited when I heard they were all alive," Mr Greenburg says.

"But it really goes to talk about the skills and the training that goes behind this stuff."

He says crews always travel very well-prepared.

"You put as much extra fuel as you can in the helicopter, you carry life rafts, everyone carries personal survival gear and you just set off and hope everything goes OK."